1. Field of the Invention
The present general inventive concept relates to a toner for developing an electrostatic charge image, a method of preparing the same, a device for supplying the toner, an apparatus and a method of forming the image using the same.
2. Description of the Related Art
Methods of preparing toner particles suitable for use in an electrophotographic process and an electrostatic charge image recording process may generally be classified into a pulverization method and a polymerization method.
Conventionally, toners used for image-forming apparatuses are mainly prepared through the pulverization method. Since the precise control of toner particle size, narrow particle size distribution, and toner shape is difficult in the pulverization method, it is difficult to independently design each property of the toner such as charging, fixation, fluidity, or storage ability.
Recently, a polymerized toner has attracted interest because control of particle diameter and shape is easy and performance of a complex manufacturing process such as classification is not necessary. When a toner is manufactured by using the polymerization method, a polymerized toner having a desired particle size and particle size distribution may be obtained without pulverizing or classification. Since a toner manufactured by using the polymerization method may have a smaller particle diameter and a narrower particle size distribution than one manufactured by the pulverization method, the polymerized toner has advantages such as high charging and transfer efficiency, high resolution through good dot reproducibility and line reproducibility, wide color gamut, low toner consumption, and high image quality. As an example of a method of preparing toner by polymerization, a binder resin, a pigment, wax, etc. are prepared in a form of particulates and an aggregation process is performed thereon after mixing the particulates to form and control a toner particle size. This aggregation process may allow control of a toner particle size and toner particle size distribution with reproducibility. Due to such a property, the aggregation process is currently being used in mass production.
In order to produce a toner having high gloss and a wide fixing latitude, a capsule-type toner prepared by controlling the aggregation process was suggested. The encapsulation of toner certainly contributes to suppression of surface exposure of a pigment and wax, thereby leading uniform charging, fluidity, and heat storage ability. For example, U.S. Pat. No. 6,617,091 describes toner particles which have a resin layer formed on a surface of a colored particle containing a resin and a colorant in order to provide a polymerized toner which has less amount of colorant on the surface of the particle and does not generate changes in image concentration, fogging, and color changes of color image caused by changes in chargeability and developability, even if the toner particles are used to form images under highly humid conditions over extended period of time. However, for example, when the toner includes a large amount of wax, heat storage ability and fluidity of the toner may be reduced because of a plasticizing effect caused by some degree of miscibility between a low molecular weight portion of the wax and the resin.
An anti-offset property of a toner is important in order to secure a stable fixing latitude of a toner. However, in general, when a printing process is performed at a higher speed, the fixing latitude is narrowed. Accordingly, the toner used may differ according to a printing process. In order to solve this problem, there is a need to develop a standardized toner whose fixing latitude is hardly changed according to the speed at which the printing process is performed.